Fishing Forecast: Chicoasén

Chicoasén, officially Presa Manuel Moreno Torres, is famous for having one of the tallest dam walls in the world at 856 feet. It sits within the spectacular Sumidero Canyon, one of the most iconic tourist destinations in Chiapas.

The dam floods part of Sumidero Canyon, creating a deep, narrow body of water with canyon walls rising up to 3,300 feet above the surface. The waters are extraordinarily deep — over 650 feet in some spots.

Fishing is done primarily along the canyon walls and where side creeks flow into the reservoir. Bass feed on rocky ledges and the shade zones created by the vertical walls.

Fishing at Chicoasén is a unique experience: casting your lure with ancient canyon walls towering around you and river crocodiles basking on the low rocks.

Fishing at Chicoasén is an experience that transcends sport. The Sumidero Canyon is a Mexican national treasure — its towering walls have witnessed thousands of years of human history, from the ancient Chiapanec civilization to the modern era. Casting a line in waters surrounded by one of the world's tallest dam walls and mile-high canyon cliffs is humbling and unforgettable.

The canyon's status as a national park means the ecosystem is actively protected. Wildlife including spider monkeys, crocodiles, and dozens of bird species share the canyon with anglers, creating a complete nature experience.

February through April is Chicoasén's best fishing window. Water temperatures in the 72-78°F range activate bass along the canyon walls and ledge systems. The narrow canyon geography means fish are concentrated in identifiable zones — rocky points, wall transitions, and creek inflows — making them easier to locate than at open-water reservoirs. Jigs and drop shots worked vertically along canyon walls are the primary techniques.

November and December provide a secondary peak as cooling water triggers fall feeding activity. Bass move from their deep summer positions to intermediate depths along the canyon walls. Crankbaits and swimbaits retrieved parallel to the rock faces produce exciting reaction strikes.

May through October presents the biggest challenge. Summer heat drives water temperatures into the mid-80s°F, and bass retreat to the deepest, shadiest canyon recesses. The saving grace is the canyon's natural shade — during certain hours, the towering walls create extensive shadow zones where bass remain active. Timing your fishing to follow the shade line as it moves across the canyon is a unique and effective strategy.

Year-round, the canyon's extreme depth (650+ feet in places) means water temperature stratification is dramatic. Finding the thermocline and fishing just above it is essential for consistent catches.

Largemouth bass at Chicoasén are canyon-dwelling specialists. Average size runs 2-3 pounds, but the deep, clear water and rocky habitat produce bass with exceptional coloring and fighting ability. Fish in the 4-6 pound range inhabit the deeper ledges and wall transitions. The vertical nature of the canyon means bass behavior is more similar to spotted bass or smallmouth than typical largemouth patterns — they hold tight to rock faces and strike baits presented precisely along the structure.

Sunfish (Lepomis spp.) occupy the shallower ledges and creek inflows, providing forage for bass. Their populations are healthy but not as dense as at more vegetation-rich reservoirs.

Freshwater snook (Centropomus spp.) are present in the lower sections of the reservoir where the water is warmer and the canyon opens up. They are an exciting bonus catch for anglers exploring the full extent of Chicoasén's waters. River crocodiles (Crocodylus acutus) inhabit the lower canyon — they are a protected species and add an element of exotic wildlife watching to the fishing experience.